The severity of the pain and disability is generally out of proportion to the findings and 70% of patients have allodynia (pain to a normally non-painful stimulus such as light touch). The quality of the pain is usually very high (usually over an 8 out of 10 - and frequently higher than a 10 out of 10) with an incongruent affect (calm or even smiling). The latter can lead to the condition being mistaken for malingering.

The criteria by Yunus and Masi for fibromyalgia in children list 4 major criteria and 10 minor criteria:

Major criteria include generalized musculoskeletal aching at three or more sites for at least 3 months, absence of a discernable underlying cause, normal screening laboratory tests, five or more typical tender points (of those listed below).

Using the Yunis and Masi criteria, children with all 4 major and at least 3 minor criteria are classified as having fibromyalgia.

What are the tender (painful) points seen in fibromyalgia (or diffuse amplified pain)?

Traditionally, patients with fibromyalgia are said to have specific 'tender points', or more correctly 'painful points' that are demonstrated when the physican pushes on specific sites. Tenderness or soreness should not be counted as a positive finding. In practice these 'painful points' are a subjective finding and therefore hard to reproduce due to inconsistency in the examiner's ability to push at the exact same location, the variable amount of pressure used in the exam and multiple host variables (having a "bad day", changes in weather, differences in symptoms at different times of day, and the appearance of symptoms before or after physical activity).

Pediatric fibromyalgia may be different from that reported in adults. Compared to adults with fibromyalgia, children seem to respond well to intense physical and occupation therapy, have long term remissions, and the condition is frequently associated with conversion symptoms and psychologic issues. Since the bulk of the literature on fibromyalgia relates to adults, it is better to use the term diffuse amplified pain rather than fibromyalgia when making this diagnosis in children. It is descriptive and bespeaks the fact the pain is real but the body amplifies it making it hurt more than typical nociceptive or injury pain.

Who gets childhood diffuse amplified pain?

Fibromyalgia in pediatric practice primarily affects preadolescent to early adolescent girls (average age 13 years, 80% females). Many patients are caucasian, middle class with a characteristic personality profile characterized as perfectionist, self-driven, high achieving, empathetic and mature beyond their years. Frequently a parent is enmeshed with the child and the pain has inordinate control over the family (e.g., parents quitting their job to care for the child).

What other disease/condition shares some of these symptoms?

Unrecognized arthritis, especially spondyloarthropathy

Hypothyroidism or hyperthyroidism

Leukemia or lymphoma

Depression

Somatization

What caused this disease to develop at this time?

The etiology is unknown but in the vast majority psychological stress plays a significant role by the time they are diagnosed. These children meet others' needs in contrast to their own and their stress seems to be resolved in the expression of their symptoms. The onset of symptoms can follow infections (influenza or mononucleosis are not uncommon) or trauma but usually the stress of the trauma is more significant than the trauma itself.

What laboratory studies should you request to help confirm the diagnosis? How should you interpret the results?

CBC, urinanalysis, CMP, ESR, and thyroid function tests are all that are necessary. Some children will have symptoms of anorexia nervosa or other eating disorders so nutritional labs (prealbumin, CMP, Zinc, Vitamin D, Vitamin E, Vitamin C level) may be indicated.

Would imaging studies be helpful? If so, which ones?

Imaging studies are not routinely indicated. If the patient has had multiple fractures or significant weight loss, a DXA scan should be done to assess their risk for fracture. In the setting of a normal neurologic examination, it is unhelpful and can be harmful to over investigate since something like a benign pineal gland cyst or Chari malformation on brain magnetic resonance imaging (MRI) in someone with headache can lead to unending worry for the patient or family or even unnecessary surgery.

Are there are clinical decision algorithms available for suspecting/confirming the diagnosis?

There is no algorithm for the diagnosis of pediatric diffuse amplified pain.

If you are able to confirm that the patient has diffuse amplified pain, what treatment should be initiated?

Laboratory and radiologic investigations should cease and medications for pain withdrawn.

Intense physical and occupational therapy needs to focus on reestablishing function, aerobic training and strengthening. If there is allodynia, then desensitization is a major part of this therapy. The therapist needs to ignore the pain complaint and not even ask about pain. They do what is hardest for the individual child so therapy varies from child to child. The type and intensity of PT/OT can vary from a minimal home exercise program to 6 hours daily for 2-6 weeks (average 3 weeks). Function usually is restored before the pain subsides and generally there is only very slow resolution.

Counseling is paramount. Initially cognitive behavioral therapy can help with coping strategies and skills but most patients should also have individual or family therapy or both. The goal is to address the underlying psychodynamics. I tell the child to talk about what they really do not want to talk about. This can lead to self-acceptance and forgiveness which are common themes. At times, other family members need individual counseling or marital therapy may be indicated.

What are the adverse effects associated with each treatment option?

When starting an intense PT/OT program, care is taken to avoid injury, especially overuse injuries such as shin splints. More overt psychopathology may emerge when the child is confronted with getting better and can be manifest with conversion symptoms, suicidality, or oppositional behavior. Rarely, sexual abuse is revealed which is always met with psychological repercussions.

What are the possible outcomes of diffuse amplified pain?

The vast majority of children become fully functional and pain will resolve in most over time. Children, and families, who continually seek a medicinal cure are frequently relegated to taking a host of powerful medications and remedies and having multiple invasive proceduals at great risk with minimal benefit.

What causes this disease and how frequent is it?

Diffuse amplified pain is becoming much more frequent and probably affects tens of thousands of American children but the prevalence is unknown. New diagnoses of amplified pain in pediatric rheumatology clinics equals or exceeds that of all the forms of childhood arthritis (there are estimated to be 90,000 to 300,000 children in the US with arthritis).

There is no seasonal variation but there are exacerbations with stress such as the onset of school or final examinations. It is rare in young children and caution should be exercised in making this diagnosis under the age of 8 years. It can follow injury, illness or be associated with stress.

Conversion symptoms frequently accompany diffuse amplified pain as do other stress related conditions. These include such things as anorexia nervosa, cutting, suicide attempts or gestures, pseudoseizures, conversion blindness, orthostatic faintness and tachycardia and irritable bowel (it is not associated with an increased incidence of celiac disease).

There are family clusters but it is unknown if this is nature or nurture.

How do these pathogens/genes/exposures cause the disease?

It is thought that in a susceptible host (stressed adolescent) that at a vulnerable period any insult (viral illness, injury, stress) will manifest with sympathetic overdrive of the autonomic system which leads to either peripheral ischemia or central sensitization and the perpetuation of an intense sensation of pain.

Other clinical manifestations that might help with diagnosis and management

Back pain in children with diffuse amplified pain is frequently associated with the non-organic signs popularized by Wadell especially axial loading, passive rotation and distracted straight leg raising.

Axial loading is positive if lower back pain is reported when downward pressure is applied to the head while the child is standing. Passive rotation is positive if the child reports pain while standing and being twisted in a manner in which the back and hips move together so there is no rotation of the back per se. Distracted straight leg raising is positive if the child reports back pain when supine and the leg is raised but not when sitting and the leg is raised causing the same degree of knee extension and hip flexion and usually distracted by focusing on the knee. In a negative (organic) distracted straight leg raising test the child will, once the leg is raised, lean back to protect the back and complain of back pain again.

In this condition, more than most, it is imperative to establish a trusting relationship with the child and family. They need to know you believe them and can be content without a pill or magic bullet treatment. It is very hard in both medicine and parenthood to do nothing. They should be instructed not to go to the emergency department for severe exacerbations of pain unless here are extenuating factors (fever) but rather take a hot bath, walk and not disturb the household.

What complications might you expect from the disease or treatment of the disease?

The worse complications are seen in those children who go on to have stress related symptoms such as eating disorders, suicide attempts, paralysis, and will subterfuge any attempt at addressing the underlying stress. Unreported sexual abuse is not rare and can have lifelong consequences.

Are additional laboratory studies available; even some that are not widely available?

For individual children, psychometric testing can be useful since there are children who have undiscovered learning difficulties that are not being met in school, therefore they are under tremendous stress trying to keep up.

How can diffuse amplified pain be prevented?

It is unknown if preventive mental health intervention would be preventative. It is impossible to avoid injury or illness.

Ongoing controversies regarding etiology, diagnosis, treatment

A controversial approach to the treatment of these children is focusing predominantly on drug treatment for pain (often using medications used in adults that are not approved for use in children) with minimal, if any, physical therapy.

Another unproven approach is to focus on the condition as a primary sleep disorder with the expectation that improving sleep will minimize the pain. Although most children with fibromyalgia have an abnormal sleep pattern there is usually not a true sleep disorder and the sleep complaints are generally not amenable to pharmacologic therapy.